The present invention relates to an automatic disk changer which houses a large number of disks such as video disks or compact disks and is manipulated outside to choose a desired disk and play it.
In a conventional automatic disk changer of such kind, pairs of guide grooves are provided on a large number of levels at one side portion of a case or at both the sides of a conveyance means, and trays containing disks are inserted in the guide grooves so that the trays can be pulled out from the grooves. A player for playing each of the disks is installed in the case at the upper or lower portion thereof. Each of the trays containing the disks can be pulled out from the guide groove by the conveyance means movable back and forth between the player and the trays and can then be conveyed to the player by the conveyance means so as to be played by the player.
Since the disks are piled up in a column at one side portion of the case of the conventional automatic disk changer or in columns at both the sides of the conveyance means, there are problems that the number of the disks which can be housed in the changer is relatively limited and the width of the case is very large. To pull out the tray from each tray guide and convey the pulled-out tray to the disk player, the depth of the case needs to be made not less than the sum of the depth of the tray housed in the tray guide and that of the tray pulled out therefrom. For that reason, there is a problem that the depth of the case is large. If a large number of disks are to be housed in the case limited in width and depth, the disks can be only piled up therein. For that reason, the height of the case is so large that there are problems that it is troublesome to place another disk in the case, and the length of the movement of the conveyance means is large, making it time-consuming to convey each of the disks to the disk player after choosing the disk.
Also, in a conventional disk automatic changer, a number of paired guide grooves are formed in a case and each tray receives the disk along the paired guide grooves.
On the other hand, a player for playing the disks is disposed in the upper or lower portion of the case. A tray transfer means is reciprocatingly moved between the player and the desired tray. The disk is pulled out from the case together with the tray by the tray transfer means to the player for reproduction of recorded information.
In addition, in the case where the tray is pulled out from the tray guide or the player by the tray transfer means, a pair of hook arms provided on the tray transfer means are engaged with engagement portions formed both on sides of the tray.
However, it is necessary to synchronously engage the pair of hook arms with the engagement portions of the tray in such a disk transfer means and it is very difficult to completely synchronize the pair of hook arms although a single motor is used in the conventional changer. Accordingly, the pair of hook arms are not synchronized with each other, so that the engagement between the engagement portions of the tray and the hook arms would be failed. The operation of the changer would not be insured.
Also, in the conventional automatic disc changer, the tray with the disk is locked to the tray guide so as to prevent the displacement of the tray relative to the tray guide within the case or the tray guide of the player.
Namely, hooks are formed in the tray guide and associated claws to be engaged with the hooks are formed in the tray. The engagement between the hooks and the claws causes the tray to be fixed to the tray guide. When the tray is pulled out by the tray transfer means, the hooks are moved by drive means such as plungers to thereby release the engagement therebetween.
However, in the means for fixing the tray to the tray guide means of the case and the disk player, it is necessary to provide for each tray guide the hooks driven by the plungers or the like, and it is necessary to provide a drive source of the plungers for releasing the engagement between the tray claws and the hooks. Accordingly, the structure of the changer is complicated, which leads to damage or breakdown of the mechanism and increases the manufacturing cost.